I just got back from a 3 day POUNDING on the Hat/McC trail system with the editor and the photographer of ATVRider mag. My Vinson held up great! Myself and my friend, on an 02 Prairie were the only guys on "utes" that could keep up with the fast group. The ATVR guys were on a Z400 and an A/C 400(same as the z400-dif plastic) and the "Banshee boys" were riding-duh, Banshees. At the Rock House trails, we were regularly hitting 50-55 on the fire roads-for extended periods. The only problem I had was at Pinnacle Creek, in Pineville. After repetedly pulling the sport quads out of the mud holes, my radiator got clogged and the Vinson got hot. After it cooled down, we hosed the fins out and it had no further problems. If you were going to ride fast n' hard with larger tires, I would invest in some better front shocks. The tires, coupled with my winch caused some bottoming on the "G-outs" at speed. It didn't unsettle the rest of the suspension, it just made an annoying "rrrruuuupppp" sound. No biggie, as there was no damage. The stock shocks are just a little soft.